/* Anti-Horizon website. A poster for the game: its own screenshots at full size, huge type, the game's navy and soft white.
   The game's mint is the third colour, kept for the things you act on and where you are on the climb. */
@font-face{font-family:"AH Sans";src:url("/fonts/inter-latin.woff2") format("woff2");font-weight:300 600;font-style:normal;font-display:swap}
@font-face{font-family:"AH Mono";src:url("/fonts/jetbrains-mono-latin.woff2") format("woff2");font-weight:400 500;font-style:normal;font-display:swap}
@font-face{font-family:"AH Display";src:url("/fonts/jost-variable.woff2") format("woff2");font-weight:100 900;font-style:normal;font-display:swap}

:root{
  color-scheme:dark;
  --void:#070e15;--void-up:#101c26;--bone:#e7ece5;--bone-soft:#a9bcb9;--ice:#e7ece5;--gold:#d8bc8d;--line:rgba(172,200,192,.2);
  --flare:#b5e6ce;
  --sans:"AH Sans","Segoe UI",system-ui,-apple-system,Arial,sans-serif;
  --mono:"AH Mono",ui-monospace,"Cascadia Code",Consolas,monospace;
  --display:"AH Display","AH Sans","Segoe UI",system-ui,sans-serif;
  --edge:clamp(16px,4vw,56px);
  --out:cubic-bezier(.16,1,.3,1);
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;background:var(--void);-webkit-text-size-adjust:100%}
body{margin:0;background:var(--void);color:var(--bone);font:400 17px/1.6 var(--sans);overflow-x:hidden}
img{display:block;max-width:100%;height:auto}
h1,h2,h3,p,ol,ul,figure,dl{margin:0;padding:0}
ol,ul{list-style:none}
a{color:inherit}
button{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--flare);outline-offset:3px}
main:focus{outline:0}
section{scroll-margin-top:72px}
.skip{position:fixed;left:16px;top:-60px;z-index:50;padding:10px 16px;background:var(--bone);color:var(--void)}
.skip:focus{top:12px}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
h2{font:500 clamp(2.5rem,6.4vw,5.6rem)/1 var(--display);letter-spacing:-.025em;text-wrap:balance;color:var(--ice)}

/* Buttons: the Play button is the one solid block of mint on any screen. */
.btn{display:inline-block;padding:15px 30px;font:600 1.05rem/1.2 var(--sans);text-decoration:none;border:1px solid var(--bone);color:var(--bone);border-radius:2px;transition:background .2s,color .2s,transform .25s var(--out)}
.btn:hover{background:var(--bone);color:var(--void)}
.btn-play{background:var(--flare);border-color:var(--flare);color:var(--void);padding:19px 44px;font-size:1.2rem}
.btn-play:hover{background:var(--ice);border-color:var(--ice);transform:translateY(-2px)}
.btn-small{padding:9px 18px;font-size:.92rem}

/* Bar */
.bar{position:absolute;inset:0 0 auto;z-index:10;display:flex;align-items:center;justify-content:space-between;gap:24px;padding:20px var(--edge)}
.bar.is-solid{position:static;background:var(--void);border-bottom:1px solid var(--line)}
.brand{display:inline-flex;align-items:center;gap:10px;font:500 1.1rem/1 var(--display);letter-spacing:.01em;text-decoration:none}
.bar nav{display:flex;gap:clamp(16px,2.4vw,34px)}
.bar nav a{font-size:.94rem;text-decoration:none;color:var(--bone);padding:6px 0;background:linear-gradient(var(--bone),var(--bone)) 0 100%/0 1px no-repeat;transition:background-size .3s var(--out)}
.bar nav a:hover{background-size:100% 1px}

/* Hero: the black hole fills the screen and the headline sits on its dark lower half. */
.hero{position:relative;min-height:100svh;display:flex;flex-direction:column;justify-content:flex-end;gap:clamp(22px,3.4vh,38px);padding:110px var(--edge) clamp(26px,5vh,52px);overflow:hidden;isolation:isolate}
.hero-shot{position:absolute;inset:0;z-index:-1;width:100%;height:100%;object-fit:cover;object-position:62% 50%}
.hero-clip{opacity:0;transition:opacity .8s}
.hero-clip.on{opacity:1}
.hero::after{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,rgba(7,14,21,.9) 0,rgba(7,14,21,.62) 34%,rgba(7,14,21,0) 62%),linear-gradient(180deg,rgba(7,14,21,.62) 0,rgba(7,14,21,0) 22%,rgba(7,14,21,0) 62%,var(--void) 100%)}
.title{font:500 clamp(3.1rem,8.4vw,8.6rem)/.94 var(--display);letter-spacing:-.035em;max-width:9.4em;text-wrap:balance;color:var(--ice)}
.hero-foot{display:flex;align-items:flex-end;justify-content:space-between;gap:32px 56px;flex-wrap:wrap}
.lead{max-width:56ch;font-size:clamp(1.02rem,1.35vw,1.2rem);line-height:1.55;color:var(--bone)}
.hero-act{display:flex;align-items:center;gap:22px;flex-wrap:wrap}
.facts{font:400 .84rem/1.4 var(--mono);color:var(--bone-soft)}

/* The climb: the screen stays while the classes rise past it. */
.climb{position:relative;background:var(--void)}
.climb-stage{position:sticky;top:0;height:100vh;height:100svh;overflow:hidden}
.climb-shot{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;opacity:0;transform:scale(1.05);transition:opacity .7s,transform 1.4s var(--out)}
.climb-shot.is-on{opacity:1;transform:none}
.climb-stage::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,var(--void) 0,rgba(7,14,21,0) 26%,rgba(7,14,21,0) 80%,var(--void) 100%),linear-gradient(90deg,rgba(7,14,21,.7) 0,rgba(7,14,21,0) 58%)}
.climb-panel{position:absolute;z-index:2;left:var(--edge);bottom:clamp(22px,5vh,46px);width:min(440px,calc(100% - 2 * var(--edge)))}
.climb-name{font:400 .86rem/1.4 var(--mono)}
.climb-mass{font:500 clamp(2rem,4.2vw,3.6rem)/1.08 var(--display);letter-spacing:-.02em;margin:6px 0 14px}
.track{height:2px;background:var(--line);margin-bottom:12px}
.track i{display:block;height:100%;background:var(--ice)}
.ladder{display:grid;grid-template-columns:repeat(22,1fr);gap:3px}
.ladder li{height:15px;background:rgba(172,200,192,.2);transition:background .3s,transform .3s var(--out)}
.ladder li.on{background:var(--ice)}
.ladder li.at{background:var(--gold);transform:scaleY(1.7)}
.climb-head{position:relative;z-index:3;margin-top:-100vh;margin-top:-100svh;padding:clamp(84px,14vh,130px) var(--edge) 0;max-width:min(900px,92vw);pointer-events:none}
.climb-head p{margin-top:18px;max-width:46ch;font-size:1.12rem}
.climb-steps{position:relative;z-index:3;padding:42vh var(--edge) 34vh}
.step{min-height:96vh;display:flex;align-items:center;justify-content:flex-end}
.evolve{width:min(380px,100%);padding:26px 28px;background:var(--void)}
.js .step .evolve{opacity:0;transform:translateY(26px);transition:opacity .6s,transform .8s var(--out)}
.js .step .evolve.in{opacity:1;transform:none}
.evolve h3{font:500 2rem/1.1 var(--display);letter-spacing:-.015em;color:var(--ice)}
.evolve-line,.evolve-mass{font:400 .82rem/1.5 var(--mono);color:var(--bone-soft)}
.evolve-line{margin:4px 0 12px}
.evolve-mass{margin-top:12px}
.step-shot{display:none}

/* Modes: a list that drives one large screen. */
.modes{display:grid;grid-template-columns:minmax(0,4fr) minmax(0,8fr);align-items:center;gap:clamp(28px,5vw,80px);padding:clamp(80px,14vh,170px) 0 clamp(80px,14vh,170px) var(--edge)}
.mode-panel{order:-1}
.mode-panel h2{margin-bottom:clamp(24px,4vh,44px)}
.mode-btn{display:block;width:100%;text-align:left;background:none;border:0;border-top:1px solid var(--line);padding:15px 0 15px 22px;cursor:pointer;position:relative}
.mode-btn::before{content:"";position:absolute;left:0;top:23px;width:9px;height:9px;background:var(--line);transition:background .2s}
.mode-name{display:block;font:500 1.4rem/1.2 var(--display)}
.mode-text{display:none;margin-top:6px;color:var(--bone-soft);font-size:.98rem}
.mode-btn:hover::before{background:var(--bone)}
.mode-btn[aria-pressed="true"]::before{background:var(--flare)}
.mode-btn[aria-pressed="true"] .mode-text{display:block}
.mode-panel .btn{margin-top:28px}
.mode-screen{min-width:0}
.mode-shot{width:100%;height:min(78vh,720px);object-fit:cover;object-position:50% 50%;transition:opacity .16s}
.mode-shot.swap{opacity:.2}

/* How to play: the game's screen at full width, and the controls beneath it. */
.how{padding:0 var(--edge) clamp(80px,14vh,170px)}
.hud-shot{position:relative;margin-inline:calc(var(--edge) * -1)}
.hud-shot>img{width:100%}
.spots{position:absolute;inset:0}
.spot{position:absolute;left:var(--x);top:var(--y)}
.spot>button{display:block;width:30px;height:30px;margin:-15px;padding:0;background:none;border:0;cursor:pointer;position:relative}
.spot>button::after{content:"";position:absolute;inset:8px;background:var(--flare);transform:rotate(45deg);transition:transform .25s var(--out)}
.spot>button:hover::after,.spot>button[aria-expanded="true"]::after{transform:rotate(45deg) scale(1.35)}
.tip{position:absolute;z-index:4;left:20px;top:16px;width:240px;padding:13px 15px;background:var(--ice);color:var(--void);font-size:.92rem;line-height:1.4;visibility:hidden;opacity:0;transition:opacity .15s}
.tip b{display:block}
.tip-left{left:auto;right:20px}
.spot>button[aria-expanded="true"]+.tip{visibility:visible;opacity:1}
.how-panel{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:24px clamp(28px,5vw,80px);padding-top:clamp(48px,8vh,90px)}
.how-panel>p{grid-column:1;font-size:1.08rem}
.how-panel h2{grid-column:1}
.controls{grid-column:2;grid-row:1 / span 2;width:100%;border-collapse:collapse}
.controls th,.controls td{padding:11px 0;border-top:1px solid var(--line);text-align:left;vertical-align:baseline;font-weight:400}
.controls th{width:30%;font:400 .84rem/1.5 var(--mono);color:var(--bone-soft);padding-right:16px}
kbd{font:400 .84rem/1 var(--mono);padding:3px 7px;border:1px solid var(--line);border-radius:2px;white-space:nowrap}

/* What you do: inverted, so the page changes key once. */
.what{background:var(--void-up);color:var(--bone);padding:clamp(80px,14vh,170px) var(--edge)}
.what h2{color:var(--gold)}
.what-head{max-width:800px;margin-bottom:clamp(36px,7vh,76px)}
.what-head p{margin-top:16px;font-size:1.12rem}
.log{columns:2;column-gap:clamp(32px,6vw,96px)}
.log li{break-inside:avoid;padding:16px 0 18px;border-top:1px solid var(--line);color:var(--bone-soft)}
.log h3{font:500 1.5rem/1.2 var(--display);letter-spacing:-.01em;margin-bottom:4px;color:var(--flare)}

/* Questions */
.questions{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,7fr);gap:24px clamp(28px,5vw,80px);padding:clamp(80px,14vh,170px) var(--edge)}
.dialog{display:contents}
summary{cursor:pointer;padding:16px 28px 16px 0;font:500 1.32rem/1.25 var(--display);list-style:none;position:relative}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";position:absolute;right:2px;top:15px;font:400 1.3rem/1.2 var(--mono);color:var(--bone-soft)}
details[open] summary::after{content:"\2212"}
summary:hover,details[open] summary{color:var(--flare)}
summary:hover::after,details[open] summary::after{color:var(--flare)}
details{border-top:1px solid var(--line)}
details p{padding:0 0 18px;color:var(--bone-soft);max-width:62ch}

/* The last screen */
.close{position:relative;min-height:92vh;display:flex;align-items:flex-end;padding:clamp(60px,10vh,110px) var(--edge);isolation:isolate;overflow:hidden}
.section-bg{position:absolute;inset:0;z-index:-1;width:100%;height:100%;object-fit:cover}
.close::after{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(180deg,var(--void) 0,rgba(7,14,21,0) 24%,rgba(7,14,21,0) 78%,var(--void) 100%),linear-gradient(90deg,rgba(7,14,21,.94) 0,rgba(7,14,21,.72) 34%,rgba(7,14,21,0) 62%)}
.close-clip{opacity:0;transition:opacity 1s}
.close-clip.on{opacity:1}
.evolve-final{width:auto;max-width:760px;padding:0;background:none}
.evolve-final h2{font-size:clamp(3rem,9.4vw,8.6rem);line-height:.94}
.evolve-final .evolve-line{margin:14px 0 12px;color:var(--bone)}
.evolve-final>p:not(.evolve-line){font-size:1.14rem;max-width:48ch}
.evolve-final .btn{margin-top:26px}

/* Foot */
.foot{display:flex;flex-wrap:wrap;align-items:center;gap:14px 36px;padding:28px var(--edge);border-top:1px solid var(--line);font-size:.9rem;color:var(--bone-soft)}
.foot .brand{color:var(--bone)}
.foot nav{display:flex;flex-wrap:wrap;gap:6px 20px}
.foot p{margin-left:auto}

/* The 404 page */
.page{max-width:760px;margin:0 auto;padding:clamp(60px,12vh,130px) var(--edge)}
.display{font:500 clamp(2.5rem,7vw,5rem)/1 var(--display);letter-spacing:-.025em;margin-bottom:18px;color:var(--ice)}
.page p{margin-bottom:20px}

@media (max-width:900px){
  .bar nav{display:none}
  .hero-shot{height:64%;object-position:64% 50%}
  .hero::after{background:linear-gradient(180deg,rgba(7,14,21,.55) 0,rgba(7,14,21,0) 18%,rgba(7,14,21,0) 34%,var(--void) 62%)}
  .modes,.how-panel,.questions{grid-template-columns:minmax(0,1fr)}
  .modes{padding-right:var(--edge)}
  .mode-shot{height:auto}
  .section-bg{object-position:70% 50%}
  .mode-panel{order:0}
  .controls,.how-panel>p,.how-panel h2{grid-column:1;grid-row:auto}
  .log{columns:1}
  .foot p{margin-left:0}
  .hero-act{width:100%}
  .btn-play{flex:0 0 auto}
  /* Phones: each class carries its own picture and the screen stops being pinned. */
  .climb-stage{display:none}
  .climb-head{margin-top:0;padding:70px var(--edge) 12px;pointer-events:auto}
  .climb-steps{padding:24px var(--edge) 40px}
  .step{min-height:0;display:block;margin-bottom:34px}
  .step-shot{display:block;width:100%;margin-top:0}
  .evolve{width:auto;padding:16px 0 0}
  .step{display:flex;flex-direction:column-reverse}
  .js .step .evolve{opacity:1;transform:none}
  .spot>button{width:24px;height:24px;margin:-12px}
  .spot>button::after{inset:7px}
  .tip,.tip-left{position:fixed;left:16px;right:16px;top:auto;bottom:16px;width:auto;z-index:20}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition:none!important}
  .js .step .evolve{opacity:1;transform:none}
}